Political fact-checkers in the U.S. are disputing many claims made by the Republican presidential candidates at their second debate as false, misleading or only marginally true.

During three hours of debate Wednesday night, 11 Republican contenders made a variety of arguments touting their own candidacies or disparaging their opponents, but the fact-checkers concluded that many of the claims were exaggerated.

The two business chieftains in the field, billionaire real estate mogul Donald Trump and former technology company chief executive Carly Fiorina, sparred over their credentials, with Trump noting that she had been fired from Hewlett-Packard. She deplored his bankruptcies.

"I never went bankrupt, by the way," Trump responded.

But, The Washington Post said that was only technically correct: Trump did not personally declare bankruptcy, but his gambling casinos along the Atlantic coast in New Jersey sought bankruptcy protection under U.S. law, which allows corporations to pay back a portion of the debts they owe, under a judge's supervision.

In the case of the casinos, where Trump owned a large portion of the companies, he was required to sell off a yacht and other personal assets under terms of court-supervised agreements.

The Post and The New York Times both said Fiorina's claims about the growth of the technology firm she headed were inflated, largely because its increased revenues were the result of Hewlett-Packard's acquisition of another technology firm.

The Post also disputed other Trump and Fiorina claims, and said Texas Senator Ted Cruz misstated key facts about the international accord about Iran's nuclear program, which he adamantly opposes.

The newspaper also disputed claims by New Jersey Governor Chris Christie that he had cut funding for the nonprofit health-care and family planning group Planned Parenthood, because of his opposition to abortion. The Post said Christie's action was related to a critical shortage of funds available to the state government in 2010.

The Times said Christie overstated the extent of what he said is a financially perilous future for Social Security, the U.S. government's largest pension program for older people.

It chided former neurosurgeon Ben Carson for wrongly stating that a border fence built in the state of Arizona blocked the flow of illegal immigrants from Mexico. The newspaper said a law-enforcement crackdown was primarily responsible for the reduction in migrants entering the United States in that area.

Another fact-checking outlet, PolitiFact, derided Trump's claim that Americans are the "only ones" granting birthright citizenship to babies born in the U.S., since 32 other nations have the same policy.

But, the organization rated as "mostly true" his claim that Florida Senator Marco Rubio has taken part in fewer Senate votes than any other member of the chamber. Rubio acknowledged that he has missed many votes during his political campaign for the Republican presidential nomination.